Decimal point mechanism



March 30, 1954 R. v. REPPERT DECIMAL POINT MECHANISM 3 Sheets-Sheet lFiled Feb. 27, 1951` IIN March 30, 1954 R. v. REPPERT DECIMAL POINTMECHANISM s 'Sheets-sheet 2 Filed Feb. 27, 1951 m. w m m M. La

March 30, 1954 R. v. REPPERT DECIMAL POINT MECHANISM 3 Sheets-Sheet 3Filed Feb. 27, 1951 INVENTOR.

Patented Mar. 30, 1954 UNITED STATES PATENT OFFICE DECIMAL POINTMEoHANIsM v Richard V. Reppert, Rochester, N. Y. Application February27, 1951, Serial N o. 212,915

` 6 Claims.

c j. 1 j

This invention relates to improvements in decimal point indicatingmechanism for calculating machine registers and more particularly forkthe class of calculating machines in which a product register havingdenominational numeral dials, adapted to be actuated to show the product,of a multiplication, is mounted in a carriage, .which is movable stepbyv step, to position the register dials relative to the denominationalactuating devices for the register dials, in the course of multiplyingoperation.

The invention consists of the novel construction and combination ofparts as set forth in the appended claims. l

The primary Objectis to provide a decimal point indicating mechanism forthe product register dials, Which-functions automaticallyto indicate thedecimal fraction ofthe figures representing a product, displayed in theregister dials, at the conclusion of a multiplying operation.

A further object is to provide a multiplicand and a multiplier decimalpoint key, both operable .in their proper sequence when operating thedigit keys of. the machine for multiplying operation. v f Another objectis to providemeans under control of the multiplicand decimal point key,to set a decimal point indicator to indicating position inthe productregister dials, which thereby indicates the decimal fraction of themultiplicand 2 figure that is being set up on the key board.

Another object is to provide an individual decimal point indicatorforeach register dial in the carriage and settable from a normallynon-indicating position to a position in which it is displayed throughan opening in the casing, to thereby indicate the decimal fraction ofthe figures representing a product.

Another object is to provide a decimal point indicator setting device,adapted to be set from a normally ineffective position to an effectiveposition, to thereby be effective to set a decimal point indicator tovisible position, in the course of .multiplying operation andsimultaneously therewith reset an adjacent decimal point indicator fromvisible position to an invisible position.

Another object is to provide a key, operable before multiplyingoperation is initiated, to set the decimal point indicator settingdevices in effective position.

Another object is to provide means under control of the multiplier.decimal point key' to reset to inenective positionthe decimalpointindicator setting device and also to induce a step movement of theregister carriage when the key is operated as the rst key of themultiplier factor, to indicate that the multiplier is a decimalquantity. A still further object is to provide a Clear key, operableupon conclusion of a multiplying operation and having means to reset toinvisible position any one of the decimal point indicators, that mayhave been set to visible position.

Other objects and advantagesof the invention will be apparent to thoseskilled in the art by the following description.

Reference is now made to the accompanying drawings wherein likereference numerals designate like parts and wherein:

Fig. l isa schematic View of the register dials and showing the variouspositions of the carriage and the decimal point indicating device in thesolution of a specific example;

Fig. 2 is a vertical section through a typical calculating machine andshowing the decimal point indicating device operating mechanism asassociated with the various operating keys;

Fig. 3is a rear view of the carriage and showing the shift mechanismltherefor; and

Fig. 4 is a partial front View of the register dials and the decimalpoint indicating members.Y

The present invention is in the nature of an auxiliary mechanism forcalculating machines, such as the commercially well-known MarchantCalculating Machine which is disclosed in U. S. Patent No. 2,320,025,issued on May 25, 1943, to H. T. Avery and as such, is not directlyconcerned with the devices functioning for calculating purposes-butobviously, can be embodied therein and be coordinated with the functionsthereof.

The said calculating machine is provided with the usual denominationalrows of multiplicand keys which are operated to set up multiplicandfactor devices which control the denominational actuatingr devices forthe registerdials. This machine is also provided with a row ofmultiplier' cated` and theletters A, -B, C, etc. indicate the variouspositions they assume in the course ofjanexample in multiplication,during which the In Fig. 1

3 register carriage is moved a step, or decimal order, from right toleft after each digit multiplication. In position A, a series of dialsnumbered I to 8 are shown and their individual decimal point indicatorsare indicated as invisible below the opening in the casing.

The multiplicand to be multiplied is 45.3 and the denominationalactuating devices for the dials line up with the register dials 2, 3 and4. As the multiplicand is being set up on the denominational rows ofkeys,"the multiplicand decimal point key is operated in its propersequence and moves the decimal point indicator for the register dial 4,to indicating position as is shown in position B. After the multiplicandhas been set up, the machine is conditioned for multiplying operation bythe operation of a key that is operated for this purpose and theoperation of this key sets a cam from ineffective to effective position,in which it cams to indicating position a decimal point indicator whenthe carriage shifts or spaces one step to the left. Position C shows thecam in effective position. The selected multiplier is 12.2 and theoperation of the l multiplier key induces the actuating devices tomultiply the multiplicand 45.3 by 1 and immediately thereafter space theregister carriageone step to the left, to thereby position the dials formultiplication by the next digit. The position D shows the positlon ofthe dials after multiplication by 1. The register carriage has moved onestep to the left and has carried thD decimal point indicator for thedial l along with it.

The next figure of the multiplier is 2 and the position E shows theposition oi' the register "I" dials after multiplication by 2 and withthe register carriage spaced one step to the left. lt will be observedthat tho decimal point indicator for the register dial l has been resetto nonindicating position and that the decimal point indicator for theregister dial 5 has been raised to indicating position. When theregister carriage moved from position D to position E, the decimal pointindicator for dial 5 was cammed up by the decimal point cani providedfor this purpose: furthermore. means are provid rid whereby the camminarup of one decimal point indicator causes resetting of the leftadiacontindicator, so that when'the indicator for the riial 5 was cammed up, theindicator for dial ll was reset toI non-indicatingr position, as isshown.

ThD next multiplier kev to be. operated is the decimal point kev andthe, rmnwtiqn f this key resets the decimal point indicator cam. toineiFectiver position, so that multiplication bv further digits will notchange the position of the decimal point indicator in the registerdials. See position li.y

The nekt multiplier digit is 2 and position GY shows the position of thedials upon completion of the multiplication. The multiplicand 45.3 hasbeen yadded twice to the product as shown in position F and then theregister carriage has s'pacedon'e more step. 4

" If the multiplier is a decimal ouantity such as .2, the vmultiplierdecimal point kev is operated first and thereby resets the cam whichsets the decimal point indicators to indicating position. As a result,the decimal point indicator for the dial which ywas set in indicatingposition whn the multiplicand 45.3 was set up, see position B,i remainsset up, but the operation of the multiplier decimal point kev, spacesthe register'carriage one step to the left and carries the indicating'decimal point indicator along, so that the denominational actuatingdevices will now line up to add the multiplicand 45.3 into the registerdials 3, 4 and 5 standing respectively thus: 0.00 and after themultiplicand is added twice the register dials 3, 4 and 5 will show9.06.

A register carriage I, schematically shown in Fig. 2, is slidablymounted on the transverse bracket 2 and is subject to step by stepmovement, between digital multiplying cycles, by any conventionalcarriage shift mechanism. These mechanisms are well known in the art,and I have shown a simple mechanism, operable by a solenoid 3 which maybe energised in any suitable manner at the termination of a digitalmultiplication, to shift the carriage to one higher decimal order. Anotched bar 4, fastened to the carriage is engaged by a `spring heldroller 5 to hold the carriage against accidental movement. A plate 6 isslidably mounted on a bracket extension 1 and carries a shift pawl 8,adapted to engage the notched bar 4, but is normally held out ofengagement therewith by bearing against a projection 9 on a fixedtransverse bar"|0 The plate 6 is 'aciuaieble asa-inst the tension` of ispring Il, by the solenoid 3 which is'subjectto energisation by aspecial key, as willbe described hereinafter.

Upon actuation of the solenoid, the pawl t engages the bar 4 and movesthe carriage until stopped by adetent I2 which is positioned to engagethe notched bar by a projection on the plate 5.

` A series of register numeral dials i6 are mounted on a shaft l1 in thecarriage and are subject to rotation by any conventional actuatingdevices to represent the product of a multiplication. The registercasing is provided with an opening I3 aligned with the active numerals*lon the dials, of which I haveshown eight, as being suflicient forillustrating the principle of operation of this invention. For such oithe numeral dialsas may be used for representing a decimal fraction of aproduct. a decimal point indicating member is provided and is mounted tothe left of the dial to which it refers. These indicating members areslid-bly mountedv on the transverse bars 2l and 22 and are held innormal position by springs" 23. vThe indicators 2D are normally belowthe line of vision through the casing opening but are subiect to upwardmovement toV become visible and thereby assume a decimal pointindicating position.` An indicating memberthus positioned, indicatesthat the register dials to the right thereof represent the decimalfraction of the product shown on the dials.

` The multiplicand keyboard is provided with a single multiplicanddecimal point key 25k which is preferably located to provide fourdecimal or-` ders for the decimal fractions part ofl thernultiplicandandthe multiplicandv is entered around this.` iixed decimal pointposition.

" `A bellcrank Z5 connectedv to `the multiplican-d key stern 2 1 has alink connection 28 ywith a set lever 2 9, underlying a decimal pointindicatingl member 2l). Uponr operation of the key 25 the respectivedecimal point indicating member is raised and in this positionwill belocked by a, spring held detent engaging a projection 3| on theindicating member.I

v'Foreachl indicatingY member adetent 30 is provided and is mounted onthe transverse shaft 35, extending between the carriage 'slide plates 36and 31.

"A multiplying operation keyV 40 isprovzided and 1S operables beforemultiplying to set the setting device for the decimal point indicatingmembers, in effective position. Upon depression of the key, a springheld detent 4| engages a projection 42 on the key stem and locks the keyand the parts actuated thereby, in set position.

A lever 44 is connected to the key stem and extends to overlie a pawl 45on a bell crank 46 which is connected by a link 49 to a lever 41 on thetransverse shaft 48 and holds it in set position.

The multiplying operation key 40 is preferably located near the rightside of the key board and so is the lever 41 on the transverse shaft 48.On this shaft, but near the center of the key board, a cam lever 5E! ismounted and has a lateral oifset formed into a cam 5|, see Fig. a, whichis positioned between adjacent decimal point indicating members, in suchmanner that the projection 52 on the indicating members will pass overthe cam upon movement of the carriage. The purpose of the cam is toraise or cam up the indicating members in succession, as the carriageshifts, step by step. When the key is operated, the cam is set ineffective position and the next shift movement of the carriage willcause the projection 52 on the decimal point indicating member to theright of the cam, to engage the cam and to move the member to indicatingposition, where it is locked by its detent.

Obviously, only one decimal point indicating member should be inindicating position to indicate the decimal fraction of the figuresshown in the register dials and therefore means are provided to reset tonon-indicating position all but one of the indicating members.

To accomplish this, every indicating member has a pin 54 extending tothe left and underlying the arm 55 of the lock detent 3) for the leftadjacent indicating member. ment of an indicating member by the cam 5I,the pin 54 thereon will actuate the pawl of the left neighbor member andrelease it'for resetting movement.

As explained by the example shown in Fig. 1, position F, the cam 5|which sets the decimal point indicators to indicating position is resetto ineffective position by the operation of a multiplier decimal pointkey 68, which is operable in its proper sequence when the multiplierkeys are operated to induce multiplying operation. As described in saidexample, the decimal point position for the figures in the product dialsis not changed, in the course of multiplying operation, after thedecimal point position of the multiplier.

A pin Si on the key stem 62 of the multiplier decimal point key overliesthe arm 63 of the pawl 45 on bell crank 45 which is actuated to set thecam in effective position. Upon operation of the key, the pawl is movedfrom under the hold.- ing extension 64 of the lever 44 and thereby the'bell crank 45 and cam 5| are free to reset under the impulse of thespring B5.

The operation of the multiplier decimal point key also induces shiftmovement of the register carriage, when the key is operated to multiplywith a decimal fraction quantity, such as .2, as explained hereinbefore.The register carriage is always in rightmost position prior tomultiplying operation and upon operation of the multiplier decimal pointkey, the key stem 62 Will close a contact 68 to thereby close a circuit-which extends to the contact 18, held in closed position by a lever 1|,when the register carriage is .ini normal or starting position. ySeeFig. 3.'y The Upon setting moveclosed circuit extends to the carriageshift solenoid which will operate the shift slide 6, to shift theregister carriage. The shift movement of the carriage opens the contact10 and thereby the circuit, so that operation of the multiplier decimalpoint key, when multiplying with a mixed quantity, will not shift theregister carnage.

Upon completion of a multiplying problem, a clear key 3l] is operated toreset the mechanism to normal position. A projection 8| on the stem 82of the key overlies the arm 83 of the lock detent 4| for the multiplyingoperation key 40, so that operation of the clear key moves the detent torelease the key, to reset.

The same projection 8| on the key stem also overlies the arm 85 of abell crank 86 which operates a lever 81 by means of a link 88. Theupward extending arm of the lever 81 is adapted to actuate a rod 89mounted in the carriage, by engaging a formed plate member thereon,extending downward and forward. The forward extension of the platemember overlies the rearward extending arms 90 of all of the lockdetents 30 for the decimal point indicating members and operation-of theclear key 80 will therefore oscillate the rod 89 and release any decimalpoint indicating member that may be in indicating position.

a register carriage with numeral dials, a carriage shifting device toimpart step by step movement to the carriage, differential actuators forthe numeral dials under control of the multiplicand key board, cyclicdrive means for the actuators, mutiplier keys sequentially operated tocontrol multi-cyclic operation of the actuators followed by operation ofthe carriage shifting device, the combination of individual decimalpoint indicators for the register dials settable to indicating position,a multiplicand decimal point key on said key board, means under controlof said key to set a decimal point indicator to indicating position,said key and said setting means having a fixed decimal order positionrelative to the rows of digit keys, thereby establishing definitedecimal orders for the rows of digit keys, a setting device for thedecimal point indicators, positioned adjacent to the aforesaid settingmeans, a key to set said' setting device from ineffective to effectiveposition in which it functions to set the register decimal pointindicators, in succession, to indicating position upon step by stepmovement of the register carriage,` means connected to each f of saidindicators, effective upon an indicator being vset to indicatingposition tocause resetting of the adjacent indicator to non-indicatingposition, these means functioning cojointly with the said setting deviceupon step by step movement of the register carriage, to thereby reset insuccession to non-indicating position all but the last set indicator, asingle multiplier decimal point key operable in its proper sequence whenthe multiplier digit keys are operated for multiplying operation andmeans under control of the multiplier decimal point key to set thesetting device for the decimal point indicators'to ineffective position.

2. In a calculating machine having 'a multi'- plicandjkey boardcomprising rows of digit keys.

a register carriage with numeral dials, a carriage shifting device toimpart step by step movement to the carriage, differential actuators forthe numeral dials under control of the multiplicand key board, cyclicdrive means for the actuators, multiplier keys sequentially operated tocontrol multi-cyclic operation of the actuators followed by operation ofthe carriage shifting device, the combination of individual decimalpoint indicators for the register dials settable to indieating position,a multiplicand decimal point key o'n said key board, means under controlof said key to set a decimal point indicator to indieating position,said key and said setting means having a fixed decimal order positionrelative to the rows of digit keys, thereby establishing deflnitedecimal orders for the rows 'of digit keys, a setting device for thedecimal point indicators, positioned adjacent to the aforesaid settingmeans, means to set said setting device from ineffective to effectiveposition. in which it functions to set the register decimal pointindicators, in succession, to indicating position upon step by stepmovement ci the register carriage, means connected to each of saidindicators, eiective upon an indicator seing set to indicating positionto cause resetting of the adjacent indicator to non-indicating position,these means functioning cojointly with the said setting device upon stepby step movement of the register carriage, to thereby reset insuccession to non-indieating position all but the last set indicator,asingle multiplier decimal point key operable in its proper sequencewhen the multiplier digit keys are operated for multiplying operation,means under control of the multiplier decimal point key to set thesetting device for the decimal point indicators, to ineffectiveposition, and means under control of the multiplier decimal point key toinduce a one step movement of the register carriage when the carriage isin its normal right most position.

3. In a calculating machine having a multiplicand key board comprisingrows of digit keys, a register carriage with numeral dials, a carriageshifting device to impart step by step movement to the carriage,diflerential actuators for the numeral dials under control of themultiplicand key boa-rd, cyclic drive means for the actuators,multiplier keys sequentially operated to 'control multi-cyclic operationof the actuators followed by operation of the carriage shifting device;the combination of individual decimal point indicators for the registerdials settable to indicating` position, a cam member settable to aneffective position in which it sets the decimal point indicators toindicating position, upon step by step movement of the registercarriage, said cam member having a fixed position relative to the rowsof digit keys, thereby establishing decimal order values to the rows ofkeys, means effective upon an indicator being set to indicatingposition, to reset to non-indicating position the indicator of adjacentdecimal order, a key to set the cam member in position, a singlemultiplier decimal point key operable in its proper sequence when themultiplier keys are operated for multiplying operation and means undercontrol of the multiplier decimal point key to reset the cam member toineffective position.

4. In a calculating machine having a multiplicand key board comprisingrows of digitkeys, av register carriage with numeral dials, a carriageshifting device to impart step bystep move-` ment to the carriage,differential actuators for the numeral dials under control of themultiplicand key board, cyclic drive means for the actuators, multiplierkeys sequentially operated to control multi-cyclic operation of theactuators followed by operation of the carriage shifting device; thecombination of individual decimal point indicators for the registerdials settable to indicating position, a setting device settable to aneffective position in which it sets the decimal point indicators toindicating position, upon step by step movement of the registercarriage, said setting device having a fixed position relative to therows of digit keys thereby establishing decimal order values to the rowsof keys, means effective upon an indicator being set to indicatingposition, to reset to non-indicating position the indicator of adjacentdecimal order, a key to set the setting device member in position, asingle multiplier decimal point key operable in its proper sequence whenthe multiplier keys are operated for multiplying operation and meansunder control of the multiplier decimal point key to reset the settingdevice to ineffective position.

5. In a calculating machine having a multiplicand key board comprisingrows of digit keys, a, register carriage with numeral dials,- a car.-riage shifting device to impart step by step movement to the carriage,diherential actuators for the numeral dials under control of themultiplicand key board, lcyclic drive means for the actuators,multiplier keys sequentially operated to control multi-cyclic operationof the actuators followed by operation of the carriage sluiting device;the combination of a series of individual decimal point indicators forthe register dials settable to indicating position, a setting device forthe indicators, normally in ineffective position and settable toeiective position, a key operable to set the setting device in eiectiveposition, means to lock said setting device in eiiective position, aclear key operable upon conclusion of a multiplying operation, to unlocksaid setting device and means under control of said key to reset tonon-indicating position any decimal point indicato-r that may be set.

6. In a calculating machine having a multiplicand key board comprisingrows of digit keys, a register carriage with numeral dials, a carriageshifting device to impart step by step movement to the carriage,differential actuators for the numeral dials under control of themultiplicand key board, cyclic drive for the actuators, multiplier keyssequentially operated to control multi-cyclic operation the actuatorsfollowed by operation of the carriage shifting device; the combinationof individual decmal point indicators for the register dials, settableto indicating position, decimal point means on said key board denotingthe iiked decimal point position thereon and thereby the xed decimalorder values of the rows of digit keys and of the actuators for theregister dials controlled thereby, a setting device for the decimalpoint indicators settable to effective position in which it sets theindicators, in succession, to indicating position upon step by stepmovement of the register carriage, said setting device being alignedwith the decimal point position of the key board and in operativerelation with the indicator that occupies the decimal point position inthe dial actuators, a key to set the setting device in eiectiveposition, means associated withsaid lindicators and effective upon` anindicator beingl RICHARD V. REPPERT.

1 References Cited in the ille of this patent UNITED STATES PA'I'EN'L'SNumber Name Date Rechnitzer Jan. 2, 1906 Bacon Aug. 5, 1924 'Blei1 Mar.31, 1931 Eller-beck Sept. 14, 1943 Reynolds Sept. 14, 1943Neumann-Lezius Apr. 17, 1951 Studley Sept. 4, 1951

